It seems peculiar. Why should the fig plant not protect its fruit until the seeds can fall to the ground? Is splitting open some unusual way of enticing animals to eat the fruit?
Slight splitting shouldn’t put you off eating a fig. It is actually quite normal and caused by humidity. Well drained land usually reduces fig splitting bug careful watering can also do the trick. If the plant gets too much water as it nears the fruiting period, The fig fruit is an extension of the tree’s stem tissue. So if it rains, or – more often – at night when evaporation is reduced, the weak structure of the fig fruit just can’t take anymore! It splits open and you wake up to disappointment!
Have no fear though. Unless you are infested with insects, freshly split figs are usually extremely tasty and just ripe enough to eat. So called “heavy” soils can also help reduce fig splitting since they tend to keep a relatively constant level of humidity. However most fig trees enjoy climates with 7 or more hours of constant sunlight, so it is never easy! Especially in the morning and the evening, sunlight and heat help get rid of dampness which would otherwise assist insects which damage the tree.
Some fig farmers claim that figs split because of rain hitting the trees. They even try to cover the fig trees with umbrellas or other systems. Others claim that particular angles of the branches with figs will keep them from splitting when it rains. It seems unlikely that it is actually the velocity of the rain drops which would cause figs to split; if this was the case, splitting would occur when we wash them under a tap too. After all that is much more water!
Figs in containers have been observed to grow too fast when they receive a lot of water, thus causing splitting in the rest of the plant which doesn’t grow as quickly.